(1). Field of the Invention
The invention relates to a cooking vessel with a container intended to receive items to be cooked, comprising an outwardly bent, encircling container margin and with a cover placeable onto the container and comprising an outwardly bent, encircling cover margin, in which the container can be closed airtight by the emplaced cover with the aid of a closing mechanism acting on the container margin and the cover margin. The closing mechanism comprises a closure ring with a C-profile cross section open radially inwardly and having inherent rigidity, extending nearly over the entire container circumference and essentially nondeformable in terms of its height, but elastically deformable in the radial opening direction. With the aid of an actuating mechanism disposed on the cover, it can be moved from an open position with greater diameter, in which the container margin is released from a lower flank of the closure ring such that the cover can be removed from the container, into a closed position with lesser diameter, in which the container margin and the cover margin are clamped together by interspacing a sealing ring between the lower, shorter, flank and an upper, longer, flank of the closure ring.
(2). State of the Prior Art
Such a cooking vessel is disclosed for example in WO-A-96 35621. Herein a cover is provided for a container with an outwardly bent, encircling container margin. The container comprises a closing mechanism acting peripherally on the margin of the container. For this purpose, at the margin of the cover, an open closure ring of metal with elastic properties is accommodated, having spring resiliency, which, upon expansion of the closure ring, increases in diameter. In its resting position the closure ring is clamped between the end region of a portion of the encircling container margin and the end region of a bent-off portion structured annularly at the cover margin. The closing mechanism comprises means to expand the diameter of the closure ring against this spring resiliency. The closure ring is a C-profile with completely continuous wall between its two ends at which the closure mechanism applies. Of disadvantage herein is that the closure ring in the closed position does not assume a completely round form, which, however, should be striven for for reasons of greatest possible safety. Of disadvantage is further that the known closure ring must comprise, on the one hand, relatively strong material in order for it to absorb pressure forces under the given operating conditions of a pressure cooker and be substantially nondeformable in terms of height, but, on the other hand, is to have the requisite elasticity and ready adjustability in the radial direction. These requirements can only with difficulty be mutually fulfilled.
It is the objective of the present invention to remedy in particular these disadvantages of the prior art, and to propose a cooking vessel of the above described type which comprises greater safety and greater operating ease without increased technical expenditures.
This objective is achieved according to a main idea of the invention, for example, by either the encircling flanks of the closure ring being provided with radial slots of given length and width open toward the inner flank margin and distributed over the circumference or the flanks being formed by C-profile segments, short in the circumferential direction, and disposed on an encircling annular connection element radially at the outside while keeping vacant interspaces distributed over the circumference.
Several advantages are thereby achieved simultaneously: due to the selection of the slots or interspaces according to length and width, the opening forces, taking into consideration optimum operability, can be adjusted without the nondeformability of the closure ring suffering in terms of height. Therefore, for the closure ring or the individual C-profile segments, a relatively large material thickness can be used in order to increase the safety of the closure. The ready operability is not impaired thereby. With the number of slots or interspaces, the approximation of the closure ring to the circular form increases, which also contributes to increased safety.
If the flanks of the closure ring are of different length, i.e., if the lower flank is shorter than the upper one, such that during a move of the closure ring toward the outside into the open position the container margin is already released by the lower flank while the upper flank is still being carried on the cover margin, by way of the difference of slot length, an equalization of the radial deformability in the upper and lower flank region can be created, whereby the slots in both flanks terminate in each instance at the same spacing in front of the C-profile back.
A further improvement of the functional safety can be attained by the closure ring being guided on a covering ring, for example detachably held with spring elements on the cover, and comprising for example a synthetic material, perpendicularly to the cover axis.
In a further embodiment of the invention the closure ring rests in its open position on an outer circumferential shoulder formed, for example, by the covering ring, and extending parallel to the cover circumference, such that it is centered on the outer circumference. This has the advantage that the inner margin edge of the lower flank of the closure ring in the open position of the closure ring only needs to have a small spacing from the corresponding margin edge of the container margin in order to ensure that the cover can be readily placed and removed.
It is further of advantage according to a further characteristic of the invention if the margin edges of container margin and cover margin, on the one hand, and the two flanks of the closure ring, on the other hand, have bent-offs facing one another, whereby not only a stiffening of the particular margins and flanks is ensured but also the reliable guidance of these elements to one another.
According to a still further embodiment of the invention the closure ring is prestressed such that in its open position it tends to decrease its diameter, to thus move automatically into the closed position unless it is intentionally prevented from doing so. This contributes to a further increase of safety.
A simple operation of the cooking vessel structured according to the invention is attained in particular if the two ends of the closure ring for the force introduction are connected with the actuating mechanism, preferably form-fittingly.
In the actuating mechanism can take place a force transmission and possible force conversion from a movement of an actuating element into a movement of the ends of the closure ring in the circumferential direction.
In order to prevent the closure ring from automatically moving from an open position into the closed position or conversely, the actuating mechanism and thus also the position of the ends of the closure ring and/or the closure ring itself can be arrestable in the open position and/or the closed position.
For reasons of safety, further, the actuating mechanism can be coupled with a neutral-pressure safety mechanism and specifically such that the actuation for widening out of the closure ring from the closed position in the direction toward opening can only be initiated if the container interior is pressure-relieved.
The actuating mechanism is usefully developed such that during its actuation for opening, first steam is released until the interior of the vessel is without pressure. Thereby a potentially provided neutral-pressure safety mechanism enables a further actuation path, the ends of the closure ring are unlatched from a locking member and the actuation element is enabled for opening the closure latch such that the ends of the closure ring can be moved apart in the circumferential direction.
The actuating mechanism can comprise a slider as the actuating element, with the aid of which the neutral-pressure safety mechanism, a rotary button for opening the closure ring as a further actuating element, and thus the ends of the closure ring, can be latched.
Further goals, characteristics, advantages and application feasibilities of the invention are evident in the following description of embodiment examples in conjunction with the drawing. All described and/or graphically depicted characteristics alone or in any combination form the subject matter of the invention, independently of their compilation in individual claims or their reference back.